MELBOURNE, Australia—Australian stem cell and regenerative medicine company, Cynata Therapeutics Limited announced today that the independent Data Safety Monitoring Board (DSMB) has recommended that Cynata’s clinical trial of its lead Cymerus mesenchymal stem cell (MSC) product CYP-001 should progress to the next stage as planned.

Cynata’s clinical trial, which is the first clinical trial in which patients have been treated with an allogeneic, induced pluripotent stem cell (iPSC)-derived therapeutic MSC product, consists of a planned total of 16 patients with steroid-resistant acute graft-versus-host disease (GvHD). The recommendation to progress to the next stage (Cohort B) followed an independent review by the DSMB of the eight participants in Cohort A. Recruitment for Cohort A commenced in May 2017, and there are currently seven trial sites active and ready to enroll participants into Cohort B.

Graft-versus-host-disease is a complication that can occur after a bone marrow transplant or similar procedure, when the donor’s immune cells attack the recipient of the transplant. The only approved treatment for GvHD is corticosteroid therapy, which is typically effective in only 50 percent of patients. When GvHD fails to improve or worsens despite steroid treatment, patients are described as having steroid-resistant GvHD. The prognosis for these patients is poor, with mortality rates in excess of 90 percent.

All eight participants in Cohort A reportedly demonstrated at least a Partial Response (defined as an improvement in the severity of GvHD by at least one grade compared to baseline). No treatment-related serious adverse events or safety concerns have been identified. The DSMB recommended progressing the clinical trial to second cohort (Cohort B), and patient enrollment in Cohort B (higher dose cohort) is now open.

Steroid-resistant GvHD patients today have a dismal prognosis, where mortality rates are very high. At this time, seven of the eight participants in Cohort A are alive. One participant died after developing pneumonia, which is a common finding in recipients of bone marrow transplants and similar procedures. This death was not considered to be treatment-related.

Participants enrolled in Cohort A of the dose-escalation trial received a dose of CYP-001 that was anticipated to be at the lower end of the effective dose range (one million cells per kilogram of bodyweight, up to a maximum of 100 million cells per infusion). In Cohort B, a further eight participants will receive two infusions of CYP-001 at a dose of two million cells per kilogram of bodyweight, up to a maximum of 200 million cells per infusion.

Dr Ross Macdonald, CEO of Cynata Therapeutics, said, “We are thrilled to report this encouraging early review of the Phase 1 trial of CYP-001, which marks the first time that patients have been treated with an allogeneic, induced pluripotent stem cell-derived therapeutic MSC product. The improvement in GvHD grade observed in 100% of these gravely ill people is very promising, especially given the low dose administered in Cohort A. The positive DSMB recommendation is an important milestone that enables us to begin enrollment in Cohort B, and advance toward our goal of completing the trial later this year. A successful outcome will support the application of CYP-001 in many medically and commercially significant targets where therapeutic MSCs have shown promising results.”

Patient enrollment into Cohort B is now open at seven active sites across the U.K. and Australia. Cynata says they look forward to providing further updates to the market as the study progresses.